ExNavigation
A route-centric, batteries-included navigation library for Exponent and React Native that works seamlessly on Android and iOS.
A few of our favorite features:
- Android back button handling (it just works, no need to do anything)
- Tab bar navigation
- Drawer navigation
- Sliding tab navigation
- Optional blurred translucent backgrounds in navigation and tab bar on iOS
- Alert bars
- Declarative configuration co-located with your routes
- Typed with Flow
Installation
npm i @exponent/ex-navigation babel-preset-react-native-stage-0 --save
- Change your
.babelrc
(if you have one, if not, then create one):
{
"presets": ["react-native-stage-0/decorator-support"]
}
Note: Comprehensive documentation is coming soon! For now, check out the example project in example/
. This lib is very much a work in progress.
How to run the example project
cd example/ExNavigationExample && npm install
- Install the Exponent client and XDE
- Open the project in XDE and open it in the Exponent client
How is this different from what is built into React Native?
NavigationExperimental
ships with React Native, it is powerful and
flexible, and that comes at the cost of exposing some internals to the
app developer. ExNavigation is built on top of NavigationExperimental
with the aim of providing a more feature-rich out of the box experience.
A minimal navigation set up
To give you an idea of what the required pieces of are, the following includes only the minimal code necessary to get ExNavigation working.
import React from 'react';
import {
AppRegistry,
Text,
View,
} from 'react-native';
/**
* If you're using Exponent, uncomment the line below to import Exponent
* BEFORE importing `@exponent/ex-navigation`. This sets the status bar
* offsets properly.
*/
// import Exponent from 'exponent';
import {
createRouter,
NavigationProvider,
StackNavigation,
} from '@exponent/ex-navigation';
/**
* This is where we map route names to route components. Any React
* component can be a route, it only needs to have a static `route`
* property defined on it, as in HomeScreen below
*/
const Router = createRouter(() => ({
home: () => HomeScreen,
}));
class App extends React.Component {
render() {
/**
* NavigationProvider is only needed at the top level of the app,
* similar to react-redux's Provider component. It passes down
* navigation objects and functions through context to children.
*
* StackNavigation represents a single stack of screens, you can
* think of a stack like a stack of playing cards, and each time
* you add a screen it slides in on top. Stacks can contain
* other stacks, for example if you have a tab bar, each of the
* tabs has its own individual stack. This is where the playing
* card analogy falls apart, but it's still useful when thinking
* of individual stacks.
*/
return (
<NavigationProvider router={Router}>
<StackNavigation initialRoute={Router.getRoute('home')} />
</NavigationProvider>
);
}
}
class HomeScreen extends React.Component {
/**
* This is where we can define any route configuration for this
* screen. For example, in addition to the navigationBar title we
* could add backgroundColor.
*/
static route = {
navigationBar: {
title: 'Home',
}
}
render() {
return (
<View style={{alignItems: 'center', justifyContent: 'center', flex: 1}}>
<Text>HomeScreen!</Text>
</View>
)
}
}
AppRegistry.registerComponent('main', () => App);
Push and popping routes
const Router = createRouter(() => ({
home: () => HomeScreen,
+ about: () => AboutScreen,
}));
class HomeScreen extends React.Component {
render() {
return (
<View style={{alignItems: 'center', justifyContent: 'center', flex: 1}}>
<Text>HomeScreen!</Text>
+ <Text onPress={this._goToAbout}>
+ Push about route
+ </Text>
</View>
)
}
+
+ _goToAbout = () => {
+ this.props.navigator.push(Router.getRoute('about'));
+ }
}
+ class AboutScreen extends React.Component {
+ static route = {
+ navigationBar: {
+ title: 'About',
+ }
+ }
+
+ render() {
+ return (
+ <View style={{alignItems: 'center', justifyContent: 'center', flex: 1}}>
+ <Text>AboutScreen!</Text>
+ <Text onPress={this._goBackHome}>
+ Go back home
+ </Text>
+ </View>
+ )
+ }
+
+ _goBackHome = () => {
+ this.props.navigator.pop();
+ }
+}
In the above example you will see that we push
and pop
routes to and
from the stack by calling those functions on the navigator
prop. This
is a prop that is passed into all components that you registered with
the router. If you need to access the navigator
on a component that
is not a route, you can either pass it in manually from your route
component use withNavigation
as a decorator on the component:
import React from 'react';
import { Text } from 'react-native';
import { withNavigation } from '@exponent/ex-navigation';
@withNavigation
class BackButton extends React.Component {
render() {
return <Text onPress={this._goBack}>Go back</Text>
}
_goBack = () => {
if (this.props.navigator.getCurrentIndex() > 0) {
this.props.navigator.pop();
}
}
}
Passing params to a route
class HomeScreen extends React.Component {
_goToAbout = () => {
- this.props.navigator.push(Router.getRoute('about'));
+ this.props.navigator.push(Router.getRoute('about', {name: 'Brent'}));
}
}
class AboutScreen extends React.Component {
static route = {
navigationBar: {
- title: 'About',
+ title(params) {
+ return `Greeting for ${params.name}`;
+ },
}
}
render() {
return (
<View style={{alignItems: 'center', justifyContent: 'center', flex: 1}}>
- <Text>AboutScreen!</Text>
+ <Text>AboutScreen! Hello {this.props.route.params.name}</Text>
<Text onPress={this._goBackHome}>
Go back home
</Text>
Updating route params
Sometimes you don't have all of the data that you need to set the
navigation bar title when you mount the route - for example, if you
navigate to a user profile screen by user id and need to fetch the
profile data before you know what the name is. In this case,
one solution is to use the updateCurrentRouteParams
function available
on StackNavigation
navigators.
class AboutScreen extends React.Component {
static route = {
navigationBar: {
title(params) {
- return `Greeting for ${params.name}`;
+ if (typeof params.isCool === 'undefined') {
+ return '';
+ }
+
+ return params.isCool ? `Hey cool person!` : `zzz`;
},
}
}
+ componentDidMount() {
+ setTimeout(() => {
+ this.props.navigator.updateCurrentRouteParams({
+ isCool: this.props.route.params.name === 'Brent'
+ })
+ }, 1000);
+ }
+
Make navigation bar buttons update based on route or app state
See the following example for details on how to connect your buttons to the navigator or Redux to perform actions: https://github.com/brentvatne/ex-navigation-conditional-buttons-example
StackNavigation actions
As you saw above, you can push
and pop
routes. The following is a
full list of functions that can be called on StackNavigation navigators.
push
: add a route to the top of the stackpop
: remove the route at the top of the stackreplace
: replace the current route with a given routeshowLocalAlert
: show an alert bar with given text and styleshideLocalAlert
: hide an active alert barimmediatelyResetStack
: reset the current stack to the given stackupdateCurrentRouteParams
: update route params as in the above example
Working with the navigation bar
The navigation bar configuration exposes a set of useful options that should allow you to do most things that you will want to do with it.
You specify the configuration for the navigationBar
on the route
component, or on a StackNavigation
component.
On a route component
When you configure the navigationBar
on a route component, the
configuration only applies to that specific component. This is
usually useful for specifying the title or components to render
on the left or right of the title.
@connect()
class SignOutButton extends React.Component {
render() {
return (
<TouchableOpacity onPress={this.props.dispatch(Actions.signOut())}>
<Text>Sign out</Text>
</TouchableOpacity>
);
}
}
class AboutScreen extends React.Component {
static route = {
navigationBar: {
title: 'Title goes here',
renderRight: (route, props) => <SignOutButton />
}
}
// ...
}
On StackNavigation
You can configure the defaultRouteConfig
for all routes within a
StackNavigation
to save you needing to specify properties like
the navigationBar
backgroundColor
and tintColor
(color to
use for the title and back button or drawer menu hamburger button).
class App extends React.Component {
render() {
return (
<NavigationProvider router={Router}>
<StackNavigation
defaultRouteConfig={{
navigationBar: {
backgroundColor: '#000',
tintColor: '#fff',
}
}}
initialRoute={Router.getRoute('home')}
/>
</NavigationProvider>
);
}
}
navigationBar properties
title
- a string or a function that returns a string. The function is provided with the route params as the first argument.titleStyle
- Text.propTypes.style object to use for the title.backgroundColor
- the background color to use for thenavigationBar
.tintColor
- the color to use for the title text and back button or drawer button icons.visible
- boolean that indicates whether thenavigationBar
should be visible for this route.translucent
- iOS and Exponent only, use background blur on thenavigationBar
, like in the Apple Podcasts app, for example.renderLeft
- a function that should return a React component that will be rendered in the left position of thenavigationBar
.renderTitle
- a function that should return a React component that will be rendered in the title position of thenavigationBar
.renderRight
- a function that should return a React component that will be rendered in the right position of thenavigationBar
.
TabNavigation
A minimal example using tabs:
import {
StackNavigation,
TabNavigation,
TabNavigationItem as TabItem,
} from '@exponent/ex-navigation';
// Treat the TabScreen route like any other route -- you may want to set
// it as the intiial route for a top-level StackNavigation
class TabScreen extends React.Component {
static route = {
navigationBar: {
visible: false,
}
}
render() {
return (
<TabNavigation
id="main"
navigatorUID="main"
initialTab="home">
<TabItem
id="home"
title="Home"
selectedStyle={styles.selectedTab}
renderIcon={(isSelected) => <Image source={require('./assets/images/home.png')} /> }>
<StackNavigation
id="home"
navigatorUID="home"
initialRoute={Router.getRoute('home')}
/>
</TabItem>
<TabItem
id="posts"
title="Posts"
selectedStyle={styles.selectedTab}
renderIcon={(isSelected) => <Image source={require('./assets/images/posts.png')} /> }>
<StackNavigation
id="posts"
initialRoute={Router.getRoute('posts')}
/>
</TabItem>
<TabItem
id="profile"
title="Profile"
selectedStyle={styles.selectedTab}
renderIcon={(isSelected) => <Image source={require('./assets/images/profile.png')} /> }>
<StackNavigation
id="profile"
initialRoute={Router.getRoute('profile')}
/>
</TabItem>
</TabNavigation>
);
}
}
See an example of TabNavigation in a real app here.
If you'd like to switch tabs programmatically (eg: a notification
arrives and you want to jump to a notifications tab, or you tap on a
button to open your profile but within another tab) you can use
jumpToTab
. For the code below to work, we need the navigatorUID
prop
to be set on TabNavigator, as with the example above.
<TouchableOpacity
onPress={() => {
this.props.navigation.performAction(({ tabs, stacks }) => {
tabs('main').jumpToTab('profile');
stacks('home').push(route);
});
}}
/>
DrawerNavigation
A minimal example using the DrawerNavigation:
import {
StackNavigation,
DrawerNavigation,
DrawerNavigationItem,
} from '@exponent/ex-navigation';
// Treat the DrawerNavigationLayout route like any other route -- you may want to set
// it as the intiial route for a top-level StackNavigation
class DrawerNavigationLayout extends React.Component {
static route = {
navigationBar: {
visible: false,
}
};
render() {
return (
<DrawerNavigation
id='main'
initialItem='home'
drawerWidth={300}
renderHeader={this._renderHeader}
>
<DrawerNavigationItem
id='home'
selectedStyle={styles.selectedItemStyle}
renderTitle={isSelected => this._renderTitle('Home', isSelected)}
>
<StackNavigation
id='home'
initialRoute={Router.getRoute('home')}
/>
</DrawerNavigationItem>
<DrawerNavigationItem
id='about'
selectedStyle={styles.selectedItemStyle}
renderTitle={isSelected => this._renderTitle('About', isSelected)}
>
<StackNavigation
id='about'
initialRoute={Router.getRoute('about')}
/>
</DrawerNavigationItem>
</DrawerNavigation>
);
}
_renderHeader = () => {
return (
<View style={styles.header}>
</View>
);
};
_renderTitle(text: string, isSelected: boolean) {
return (
<Text style={[styles.titleText, isSelected ? styles.selectedTitleText : {}]}>
{text}
</Text>
);
};
}
const styles = StyleSheet.create({
header: {
height: 20
},
selectedItemStyle: {
backgroundColor: 'blue'
},
titleText: {
fontWeight: 'bold'
},
selectedTitleText: {
color: 'white'
}
});
Integrate with your existing Redux store
Behind the scenes ExNavigation manages your navigation state using
Redux in its own store. If you'd like to store the navigation state
on your app's store, you can use the createStoreWithNavigation
function when creating the store and then manually provide the
NavigationContext
, initialized with your app's store.
/* Your store definition, let's say state/Store.js */
import { createNavigationEnabledStore, NavigationReducer } from '@exponent/ex-navigation';
import { createStore } from 'redux';
const createStoreWithNavigation = createNavigationEnabledStore({
createStore,
navigationStateKey: 'navigation',
});
const store = createStoreWithNavigation(
/* combineReducers and your normal create store things here! */
combineReducers({
navigation: NavigationReducer,
// other reducers
})
);
export default store;
/* Your routes, Router.js */
export const Router = createRouter(() => ({
home: () => HomeScreen,
}));
/* The top level of your app, often in main.js or index.[ios/android].js */
import {
createRouter,
NavigationContext,
NavigationProvider,
StackNavigation,
} from '@exponent/ex-navigation';
import Store from './state/Store';
import Router from './Router';
const navigationContext = new NavigationContext({
router: Router,
store: Store,
})
return (
<Provider store={Store}>
<NavigationProvider context={navigationContext}>
<StackNavigation yourUsualPropsHere />
</NavigationProvider>
</Provider>
)
Perform navigation actions from outside of a component
You might be using some Redux middleware like saga, thunk, promise, or
effex (we recommend effex
because we love async/await
). Whatever you're using, you no longer
have access to this.props.navigator
and the like. What to do?
Well as long as you include your navigation state inside of your Redux
store, you can dispatch a NavigationAction to it -- after all, this is
what this.props.navigator.push
etc. do behind the scenes.
In the following example we call getState
and dispatch
directly on
your store -- feel free to change this to whatever the equivalent is
for your context (eg: if this was effex, dispatch
and getState
would
be passed in to the goHome
function).
import { NavigationActions } from '@exponent/ex-navigation'
import Store from '../state/Store';
import Router from './Router'
export default function goHome() {
let navigatorUID = Store.getState().navigation.currentNavigatorUID;
Store.dispatch(NavigationActions.push(navigatorUID, Router.getRoute('home')))
}